Furnace for steam-boilers



No. 68,785. Patented Nov. 8, I898. H. SIEBEN.

FURNACE FOR STEAM BOILERS.

(Application filed Apr. 25, 1898.)

(No Model.)

THE NORRIS PETERS cm. mum-Luvs. WASHINGYON. v. c

NITED STATES HENRY SIEBE-N, or

CHICAGO, ILLINOIS.

FURNACE FOR STEAM-BOILERS.

SPECIFICATION formingpart of Letters Patent No. 613,785, dated November 8, 1898.

Application filed April 25, 1898. Serial No. 678,739. (No model.)

To all whom it may concern:

Be it known that I, HENRY SIEBEN, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a new and useful Furnace for Steam- Boilers, of which the following is a specification.

This invention relates to furnaces for steam-boilers.

The object of the invention is to provide a furnace for steam-boilers of simple and improved construction and wherein thegases, smoke, and other products of combustion are maintained incandescent, and hence are completely consumed.

Further objects of the invention will appear more fully hereinafter.

The invention consists, substantially,in the construction, combination, location,and relative arrangement of parts, all as will be more fully hereinafter set forth, as shown in the accompanying drawings, and finally specifically pointed out in the appended claims.

Referring to the accompanying drawings and to the various views and reference signs appearing thereon-- Figure 1 is a View in Vertical transverse section of a furnace constructed in accordance with and embodying the principles of the invention, the plane of section being on the line 1 1, Fig. 2, looking in the direction of the arrows. Fig. 2 is a broken horizontal sectional plan view of the same on the line 2 2, Fig. 1, looking in the direction of the arrows. Fig. 3 is a broken detail view of the same in vertical longitudinal section. Fig. 4 is an enlarged detached detail View in elevation of the furnace-chamber door. Fig. 5 is a trans verse sectional View of the same on the line 5 5, Fig. 4, showing the relative location and arrangement of the air-spout carried thereby. Fig. 6 is a detached detail View, slightly in perspective, of the air-spout carried by the furnaoechamber door.

The same part is designated by the same reference sign wherever it occurs throughout the several views.

In the drawings, reference sign 7 designates the framework of the furnace and which may be constructed of suitable brick or masonry work and suitably arranged to support the boiler 8. The fire grate 9 is mounted and chamber practically the entire length of the grate-bars or surface 9 on each side thereof, as clearly shown in Figs. 1 and 2, and from the top edge of the fire box or chamber to a point below the fire grate, thus forming chambers or passages between the fire-chain ber and the inner walls of the framework 7. Suitable dampers 11, arranged beneath the grate, are provided for the purpose of controlling these chambers or passages. The side walls 12 of the fire-box are arranged to extend vertically from the grate-surface 9. These side walls extend the entire length of the grate-surface and are constructed of firebrick or other suitable refractory material and form one of the inclosing walls of chambers or passages 10. At or adjacent to the top edges of the side walls 12 said walls are provided with a series of openings or perforations, as indicated at 13.

From the construction above described it will be readily seen that in addition to the usual air-draft which reaches the fuel in the fire-box through and between the grate-bars air-drafts are maintained from the ash-pit through chambers or passages 10 and apertures or openings 13. From the location of these apertures at or adjacent to the tops of side walls 12 of the fire-box it will be readily seen that the air-drafts supplied therethrough to the fire-box are supplied at a point above or adjacent to the top of the bed of fuel, and hence intermingles with the flame arising from the bed of fuel, thus furnishing oxygen at a point where it is required to efiect a complete combustion of the gases, smoke, and the like arising from the bed of fuel. It will also be seen that this draft of air is not supplied in a manner to hasten the consumption of fuel in the fire-box, as the draft through the grate surface and from beneath the bed of fuel does; but on the contrary the draft of air through chambers or passages 10 is supplied above the bed of fuel, and hence operates merely to maintain the gases, smoke, and other unconsumed products of combustion in a state of incandescence in the flame arising from the fuel, and hence effecting a complete combustion thereof. It will also be seen that as chambers or passages 10 are formed on both sides of the fire-box these side drafts of air cover the entire surface of the bed of fuel on both sides.-

In order to still further effect the object of supplying oxygen in the shape of air to the fire-box and at a point where such supply is desirable in order to maintain the gas, smoke, and other unconsumed products'of combustion in a state of incandescence without unduly hastening the combustion of the fuel, I arrange in the fire-chamber at the rear end thereof a hollow air-box 14, extending from the grate-surface upwardly to about or above the top of the fuel. At or about the top of this air-box I provide perforations 15 through the walls thereof. A cap 16 serves to close the top of the air-box, while the lower end of the hollow chamber of said box opens, as at 17, into the ash-pit. This air-box may be constructed of fire-brick or other suitable refractory material, and its purpose is to supply jets or drafts of air at a point about the middle of the fire-chamber at the rear end thereof and above the bed of fuel, and being located about midway the transverse width of the fire-chamber it will be seen that air is supplied at a point which is not efiectively reached by the air entering from the sides of the fire box through chambers or passages 10. It will also be seen from the location of airbox that the air supplied therethrough enters the fire-chamber at a point above the bed of fuel and where the flame is hottest, and intermingling and spreading through such flame causes the gases, smoke, and unconsumed particles of combustion to become incandescent, and hence to be consumed.

In order to still further provide for a supply of air to the flame of the fuel, so as to insure a complete combustion of all the products of combustion, which would otherwise be carried ofi up the smoke-stack or chimney, I provide an angle bar 18 and arrange the same transversely of the furnace chamber, at the rear thereof and somewhat in advance of the fire-arch or bridge-wall 10. The rear end of the grate 9 is supported upon this angle-bar, as clearly shown in Fig. 3. Preferably the surface of the fire or bridge wall 19 directly opposite angle-bar 18 is inclined upwardly and forwardly, as clearly shown at 20. In order to suitably ofiset the angle-bar 18 from the fire or bridge wall and to form a support for said angle-bar to prevent the same from being crowded or pushed back against the fire-wall 19, I interpose suitable brackets or spacing blocks 21 between said angle-bar and fire-wall. These blocks or brackets are spaced a distance apart suflicient to leave passages or openings 22,through which air may ascend from the ash-pit.

This

Figs. 5 and 6.

ascending draft of air impinges against the inclined surface 20 of the bridge-wall and is thereby deflected forwardly over the rear edge of the bed of fuel and into the flame at the point where any unconsumed particles of smoke or gases are about to be carried off up through the flue to the chimney, as indicated by the arrows, thus insuring a complete combustion of every particle of smoke or gas.

In the foregoing description I have described how air is supplied to the fire-box above'the bed of fuel at the sides and rear end of the fire-chamber. It is desirable also to supply air above and over the bed of fuel from the front end of the fire-box in carrying out the principles of my invention. In order to accomplish this result in a simple and efficient manner, I provide the fire-chamber door 23 with an air-spout 24, inclined upwardly and inwardly, as clearly shown in The door 23 may be provided with the usual slide 25 to regulate the supply of air therethrough. From this construction it will be seen that a draft of air is efficiently maintained from the front of the firechamber upwardly over the bed of fuel, thus aiding in effecting a complete combustion of the products of combustion arising from the bed of fuel.

In order to distribute the heat equally throughout the length of the boiler and to prevent the boiler from being subjected to too great a heat at only one point, I interpose a shield,-in the form of a plate 26, between the boiler and the hottestpart of the fire. As shown, this shield or plate extends from a point a little distance to the rear of the front of the fire arch or wall 19, forwardly therefrom over the place where the fire is hottest. This plate not only serves to prevent the boiler from being subjected to too great heat at this point, but also serves to spread the heat and evenly distribute it throughout the length of the boiler, thereby securing a uniform generation of steam in the boiler.

From the foregoing construction it will be seen that air is supplied to the fire-box from all sides thereof and at a point above the bed of fuel, and hence, instead of increasing or hastening the consumption of fuel, operates as a blanket to hold the unconsumed products of combustion as they arise from the bed of fuel in the flame, thus maintaining such particles in a state of incandescence until they are completely consumed. Moreover, by surrounding the fire-chamber with air-passages I not only secure complete combustion of the gases and smoke arising from the bed of fuel, but I also keep the inclosing walls of the fire box at a lower temperature than would other wise be the case, thus preventing a rapid burning out of the fire bricks or other material employed in the construction of the furnace, and this, too, without decreasing the steam-generating power of the heat developed in the furnace-chamber. Moreover, as I have found in practice, a furnace constructed in accordance with and embodyingthe principles of my invention, as above described, is practically smokeless, and the flues and passages leading from the furnace-chamber and up the chimney are practically free from deposits of soot. 4

Many variations and changes in the details of construction and arrangement of parts would readily suggest themselves to persons skilled in the art and still fall within the spirit and scope of myinvention. I do not desire, therefore, to be limited or restricted to the exact and specific details of construction and arrangement herein shown and described; but,

Having now set forth the object and nature of my invention and a form of apparatus embodying the principles thereof, and having described the construction, function, and mode of operation thereof, whatI claim as new and useful and of my own invention, and desire to secure by Letters Patent of the United States, is-

1. In a boiler-furnace,the combination with a grate, of an air-box arranged at the rear end of said grate and extending upwardly from said grate to a point above the bed of fuel,

said air-box being hollow and communicating at its lower end with the ash-pit beneath the grate, the upper end of said box being closed, said box being perforated in the side walls thereof at its upper end, as and for the purpose set forth.

2. In a boiler-furnace, a bridge-wall, an angle-bar arranged transversely of the furnace-chamber a slight distance in front of said bridge-wall, a grate-surface having its rear end supported by said an gle-bar, and spacing blocks or brackets interposed between said angle-bar and bridge-wall, thereby forming air-passages from the ash-pit around and over the rear end of the grate-surface, as and for the purpose set forth. i

3. In a boiler-furnace, a bridge-wall, an angle-bar arranged transversely of the furnace-chambera slight distance in front of said bridge-wall, said bridge-wall provided with a surface inclined upwardly and forwardly opposite said angle-bar, a grate-surface supported at its rear end on said angle-bar, and spacing-blocks interposed between said anglebar and the adjacent surface of said bridge- Wall, as and for the purpose set forth.

4:. In a boiler-furnace, a furnace-chamber and a boiler, in combination with a horizontally-arranged sheet or plate interposed between the boiler and the furnace-chamber above the bed of fuel and at the point where the fire is hottest, whereby the boiler is protected against too great a heat at that point, and the heat is distributed throughout the length of the boiler, as and for the purpose set forth.

In Witness whereof I have hereunto set my hand this 12th day of April, 1898, in the presence of the subscribing witnesses.

HENRY SIEBEN.

Witnesses:

HENRY A. GATES, S. E. DARBY. 

